Inexpensive absorbents for spills of crude and other oils from which the oil may easily be separated and recovered, or in the alternative which may be burned together with the oil as a fuel, which are readily dispersible and which float when saturated have been sought for some time.
Cellulosic pulps derived from many sources treated in various ways to enhance their oil absorbancy and reduce their tendency to absorb water and ultimately sink have been examined.
Canadian Pat. No. 982,951 describes chemically pulped, conventionally fluffed wood pulp treated with hydrophobic sizing. This patent also discusses other prior art relevant to it in this area.
The treatment of wood pulp and other cellulose pulps with various materials even such relatively inexpensive hydrophobizing material as rosin size adds extra process step costs and extra material costs to the expense of the prior art suggested absorbents.
Without these treatments it has always been considered that fluff pulp derived from wood pulp either chemically or mechanically would have too little oil absorption capacity and would absorb water too rapidly, thereby sinking, to be useful in oil spill control functions.
Methods for drying pulp by heat and producing fluffed pulp are known.
U.S. Pat. Nos. 3,497,418; 3,627,630; and 4,065,347 are illustrative thereof.
Copies of the cited United States patents and the cited Canadian patent accompany this application for the Examiner's convenience.